Banging pipes.

[Humph]

I have recently replaced a faulty rad in my daughters bedroom.The pipes in my house are 10mm microbore and directley below the floor in her bedroom is a manifold.I have run 2 new pipes from this and put a valve at each end as b4 the pipes were both connected at the same side of the rad creating what i think is called flow and return.Since i have done this i have noticed a clicking sound in the pipes in another bedroom directly aft heating comes on 4 about 30 sec.Also when hot water tap on bath is opened i get a loud banging.Could this be related and is it ok to change pipes on rad 2 [flow and return?]..My boiler is a Alpha CB24X combi and was fitted about 18mths ago....

 

[Bahco]

Have you fitted a trv on this rad the wrong way. Check whether it is a bi directional flow valve.
Have you allowed for expansion on your new pipe runs. Make sure they are not too tight against joists and do they need some insulation where they touch the joist.
Pipes may need some support too

 

[Humph]

I will try fitting insulation,thanx..Not sure what "bi" or "trv" valves are though,the ones i fitted are standard 10mm compression valves i think.Ive put the same on both ends of rad and are both open..

 

[BigSteve]

TRV - thermostatic radiator valve, controls the temp. in a room by automatically shutting off flow of water to the rad. It is set by turning a numbered knob on the valve until the desired temp is achieved. Bi-directional - can be fitted either way around. Some TRV's can only be fitted one way round.
You probably have some air in your system from fitting the new rad. This is what the clicking sound is. Are any of the rads cold at the top but hot lower down? If they are then bleed them. It doesn't matter how the rad is plumbed in, there is always a flow and return.

 

[Humph]

Ive bled all the rads and they r ok,they get hot very quickly.I was thinking about draining system again.The valves i fitted have an arrow on the top with a + and - at each end and 10 bar written in between.Thanx 4 your reply.....

 

[Humph]

Have now insulated all new pipes and have double checked all rads for air but still getting knocking noise when heating fires up,it starts off quite fast then slows down and seems to be coming from under floor nxt to boiler..Not sure if its getting louder or im getting more paranoid,the wife thinks ive gone mad!!